1. Field of the Invention
This invention relates to building constructions and especially to prefabricated building blocks adapted for the construction of retaining walls.
2. Discussion of Related Art
In the landscaping of private residential, industrial, commercial and public properties there are often hillsides to be considered. While some hillsides can be and often are seeded to grass or planted with ground cover of shrubs, there are many instances where the steepness of the hillside precludes any such type of planting. Steep slopes of all kinds offer an exciting opportunity for unique planting effect, but excessive water run off and consequent undesirable soil erosion prohibits such planting unless accompanied by the use of a retaining wall structure. As well as providing a more level area for planting and living space, retaining walls are often used by property owners to define the boundaries between adjoining properties. For these and other reasons, architects, builders, landscape architectors, contractors and home owners all desire to control the hillside with a structurally sound, strong retaining wall and to provide more beautiful landscape planting.
Included in the many suggested forms of retaining blocks are those shown in U.S. Pat. No. 2,960,797, issued Nov. 22, 1960 to Frehner. The Frehner patent discloses a system of identical blocks which are used in single block heights and terraced back for the next level of block. U.S. Pat. No. 3,269,125, issued Aug. 30, 1966, to Moore, shows a hillside stabilizing construction comprising header blocks and stretcher blocks which are disposed in an interconnected manner to produce a terrace retaining wall structure wherein the different levels are held together and affixed to the ground by means of steel rods which extend through openings in the various blocks into the surrounding earth. U.S. Pat. No. 3,389,499, issued June 25, 1968, to Haile, shows a system of open bottom box-type blocks that stack vertically to form a free-standing wall which acts as a divider or screen and in which vegetation may be planted to enhance the aesthetic appeal of the device. U.S. Pat. No. 3,503,589, issued Mar. 31, 1970, to Moore, shows a construction unit having at least one vertically elongated wooden or concrete post of relatively small cross-sectional area that is sunk into the ground and fixed to a wide panel by the use of nails, nuts and bolts, glue, liquid asphalt, or the like.